Profile of osteoarthritic patients undergoing hip or knee arthroplasty, a step toward a definition of the "need for surgery".

AIMS: The objective of this study is to characterize, based on clinical, radiographic, health-related, quality-of-life-related, and demographic variables, the profile of a large, homogeneous, cohort of patients undergoing knee or hip arthroplasty, in a public hospital. Current regulatory guidelines for structure-modifying agent are not clear regarding hard clinical endpoint. The "need for surgery" has been suggested as a potential relevant outcome, but, until now, it is poorly defined. By characterizing a large number of patients who undergo total hip or total knee replacement, this paper aims at providing a contribution to the better definition of the "need for surgery" in advanced OA of the lower limbs.

METHODS: Consecutive patients who underwent primary knee arthroplasty (KA) or hip arthroplasty (HA) between December 2008 and February 2013, in an academic hospital, and who were diagnosed with hip or knee osteoarthritis (OA) (ACR criteria). Data collected at baseline included demographic and clinical data; Kellgren-Lawrence radiological grading; Western Ontario and Mc Master Universities Arthritis Index (WOMAC); EuroQol five dimensions questionnaire and EuroQol visual analog scale; and 36-item Short Form Health Survey.

RESULTS: 626 subjects were included, 346 with hip OA and 280 with knee OA. Significant differences between subjects in need of an HA or of a KA were seen in terms of age (66.5 years versus 65 for hip), duration of complaints (2188 days versus 1146.5 for hip), BMI (28.68 kg/m² versus 27.07), radiological status (severe OA were found in 79.85% in knee group and 68.73% in hip group), comorbidities (FCI higher in knee group), traumatic of surgical history (37 versus 6%), and health-related quality of life and function (patients with HA had a poorer clinical status regarding WOMAC and WOMAC subscale).

CONCLUSION: Significant differences were observed between patients undergoing KA or HA. These differences might be useful to better understand the "need for surgery" status in these indications. This concept may help to define responders and failures to pharmacological treatment of OA.